As a power conversion device of this type, for example, a three-level power conversion device that is constituted by constituting a power conversion circuit for one phase and including such power conversion circuits for three phases has been proposed (see, for example, JP 2014-36509 A). In the above, the power conversion circuit for one phase is constituted with a 2-in-1 module that is constituted by connecting, in series, a first IGBT to which a flyback diode is connected in inverse parallel and a second IGBT to which a flyback diode is likewise connected in inverse parallel and containing the connected IGBTs in one package and a bidirectional switch module that contains, in a package, a bidirectional switch, which has a characteristic of allowing a current to flow in both directions.
In the conventional art described in JP 2014-36509 A, on a cooling fin, a first region in which three 2-in-1 modules are arranged in parallel and a second region in which three bidirectional switch modules are arranged in parallel are formed. The respective 2-in-1 modules and bidirectional switch modules and capacitors are electrically interconnected by a laminated bus bar.